title: Evaluation of deuterium labeled and unlabeled bis-methyl glutathione combined with nanoliquid chromatography-mass spectrometry to screen and characterize reactive drug metabolites.
abstract: We present a reactive metabolite detection assay based on the use of deuterium labeled/unlabeled bis-methyl glutathione (GSH) esters (GSH(CH(3)/CD(3))(2)) and nanoliquid chromatography coupled online with electrospray ionization tandem mass spectrometry (nLC-ESI-MS/MS). Compared with glutathione, neutralization of the carboxylic acid groups by esterification introduced a mass difference of 6, which facilitated the identification of trapped metabolites and improved the intensity of the mass spectrometry signal in positive ionization mode. The peptides allowed for the trapping of soft electrophilic reactive metabolites generated in vitro by incubation with acetaminophen, carbamazepine (CBZ), NADPH, and microsomes.
authors.affiliation: Department of Pharmacology, Université de Sherbrooke, Sherbrooke, QC, Canada.
authors.forename: Daniel
authors.initials: D
authors.lastname: Defoy
authors.forename: Patrick M
authors.initials: PM
authors.lastname: Dansette
authors.forename: Witold
authors.initials: W
authors.lastname: Neugebauer
authors.forename: J Richard
authors.initials: JR
authors.lastname: Wagner
authors.forename: Klaus
authors.initials: K
authors.lastname: Klarskov
mesh_terms: D000082:Acetaminophen / Q000737:chemistry / Q000378:metabolism*; D000818:Animals; D002220:Carbamazepine / Q000737:chemistry / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D003903:Deuterium / Q000737:chemistry; D041961:Deuterium Exchange Measurement; D004951:Esterification; D005978:Glutathione / Q000031:analogs & derivatives* / Q000032:analysis; D007553:Isotope Labeling; D008297:Male; D008861:Microsomes / Q000378:metabolism; D009249:NADP / Q000737:chemistry / Q000378:metabolism; D036103:Nanotechnology; D051381:Rats; D017207:Rats, Sprague-Dawley; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
chemical_list: D002220:Carbamazepine; D000082:Acetaminophen; D009249:NADP; D003903:Deuterium; D005978:Glutathione